Might have all kinds of reasons, your smartphone’s cpu being one of them of course. Win95 is terribly buggy, it’s a miracle it’s even working so well. Just some things off the top of my hat:
– The choppiness you’re describing, does it persist while the unit is selected? Or does it vanish after you have selected the unit?
– And the frame limit you’re describing, are you referring to frameskip? Higher values should increase performance, and smooth out sound playback at the cost of visual quality.
– Are you using fixed cycles? If so, the game will become choppy when the cycles setting overloads your cpu. In that case, set cycles=max in expert settings (cycles=max 105% for even higher performance).